Field of the Invention
The present invention relates to a control apparatus and a control method for the control apparatus.
Description of the Related Art
Conventionally, when discarding a storage apparatus such as a hard disk apparatus (hereinafter a hard disk apparatus is used as an example of a storage apparatus) mounted, for example, in a personal computer (PC) or a printer, data in the hard disk apparatus is deleted to prevent leakage of confidential data. However, it is increasingly common to completely delete data using a process of overwriting the files on a predetermined number of times with specific pattern data in addition to deletion of file management data in the hard disk apparatus.
Recently, enhanced security awareness has caused, other than when hard disks are discarded, a need for overwrite-deletion by a printing job unit of the operation region in the hard disk apparatus including intermediate data generated in processing steps and print data from the print processing steps.
A conventional overwrite-deletion method is configured so that a central processing unit (CPU) that manages the system generates pattern data on a memory to thereby enable use of the pattern data to overwrite a file in the hard disk apparatus on a predetermined number of times.
However, when the size of the file to be deleted by overwriting is extremely large or when a consecutive region on the memory cannot be ensured, a large load is placed on the CPU by use of an inefficient method in which the above process is repeated many times.
In addition to the conventional method above, a method executing an overwrite-deletion process has been discussed in Japanese Patent Application Laid-Open No. 2005-346306, by adding overwrite-deletion conditions to file management information managed by a file system of an operating system (OS).
In the method discussed in Japanese Patent Application Laid-Open No. 2005-346306, a hard disk controller is provided between a CPU for managing the system and the hard disk apparatus. When file management information stored in the hard disk apparatus is updated, overwrite-deletion conditions stored in the file management information are read out by the hard disk controller. The hard disk controller itself uses the overwrite-deletion conditions to execute overwrite-deletion processing.
Thus, the load on the CPU managing the system is reduced and overall processing efficiency of the system is improved by a configuration in which only updated management information is written into the hard disk apparatus.
However, the method discussed in Japanese Patent Application Laid-Open No. 2005-346306 uses extension of the file management information of the file system.
In recent built-in apparatuses such as printers, complexity of the configuration is increased, and often they are configured by a plurality of OS. Since a range of OS types from built-in OS to general purpose OS are used, technical and other situations arise due to the dedicated extension of the file management information.
Furthermore, since the hard disk controller is to rewrite the file management information, when a mirroring system is configured using a plurality of hard disks, control operations are complicated because the same management information for a plurality of objects is to be updated. Consequently, there are difficulties for application of the method, which is discussed in Japanese Patent Application Laid-Open No. 2005-346306, to a wide range of system configurations.